Hand-propelled hydraulic lifting truck



March 18, 1952 J, H. KLASSEN HAND-PROPELLED HYDRAULIC LIFTING TRUCK Filed Dec. 9, 1949 2 SI-IEETS--SHEET l A m w 1N..

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maw; wm/zz Mmmm ATTORNEYS 2 SHEETS-SHEET 2 INVENTOR ATTORNEYS J. H. KLASSEN mw l vm MN March 1s, 1952 Filed Dec. 9, 1949 Patented 'Man 18, 1952 `l) N I T E D STAT ES 'PATEN T 'OF FICE HAND-PROPELLED HYDRAULIC LIFTING TRUCK o J olmH. Klassen, Inman, Kans.,

Application December 9, 19.49, seriarNoflsims z claims. (o1. 2514-10) zontal, hydraulically operated lifting platform which, when in its lowermost position, will en'- gage under a conventional skid or low table only about eight inches high vfrom the noor.

A still further vobject of the invention'is to provide .a `lifting truck of the above-mentioned character which is very easy to operate, 'fand which should Yberelatively inexpensive to vrnanufacture.

Other objects andadvanta'ges of the invention will be-apparent `during the course of the following description. v

.In the accompanying drawings forming a part of this application-and in which like numerals are employed to designate like parts throughout the same:

Figure 1 is `a plan View of a lifting truck embodying my invention;

Figure .2 is aside elevation of the same;

. Figure 3 is a central, vertical, longitudinal .section taken on line 3-3 of Figure l;

Figure 4 is a transverse, vertical section taken on line 4 4 of Figure 3;

Figure 5 is a similar `section taken on line 5--5 of'Figure 3; 'and Figure 6 is 'a transverse, vertical 'section taken on line 6-6 of Figure 3, parts omitted.

In the drawings, where, for the purposefo'f illustration, is'shown a preferred embodiment vof my invention, the numeral l designates generally :a horizontal supportframe of'welded construction.

vThis support frame I llfcomprise's a pair `of ytransversely spaced, longitudinal, outer bars vor sides I'I, which are straight throughout the majorportion of their length, 'and bent'ne'ar their forward vends to 'form forwardly converging motions I2, *y

in turnbent at `their forward ends to form vopposed, laterally spaced, short longitudinal extensions I3. lThe rear ends of the vsides or rbars II are rigidly secured together `by a transverse end bar I having its opposite ends welded to the adjacent-ends 'ofthe bars .I I. A pairpinner,

ilongtudnal, horizontal' bars m'als liliana pair' 'of ends rigidly secured to the `transverse bar I`4'by welding, and the opposite ends of 'the bars I are rigidly secured to the forward ends -the bars II and I5 are parallel.

` tensions of lthe lconverging portions or sections I2 by welding. The inner bars I5 are spaced laterally inwardly from the vouter 'bars II, as shown, vand I5 are lin longitudinal alignment with the exvI3. Arranged near the longitudinal centers of the innerbars I5 and extending trans- =aversely between such bars is a transverse brace bars I5. "stitute a unitary, low, rigid, horizontal frame or "bar I6 having its opposite ends Welded to the The elements thus far described-conwhich is-generally rectangular and elongated, as shown .in Figure 1.

A transverse, horizontal shaft or Aaxle I1 -is arranged near and 7inwardly of the transverse end bar I4, vand is rigidly 'secured within aligned itendsorthe entire distance between the outer bars II. Rotatably mounted upon the axle I1 between thepairsof'bars I"I and I5 are pairs of wheels -or rollers' I8 which may be formed lof hard `-rubber orrsteel. The 'wheels I8 are o'f such diameter that they supportthe `adjacent Aend of thehorizontalframe I0, preferably approximate`- "support frame.

ly two inches above the oor.

A `bodyor casing I9 isrigidly secured 'byweld- `ing to the vsections I'2..and extensions vI3 `of the The .bottom of tha casing I9 is "open, and the casing projects above the support frame I8. as shown. The body or casing 19includes fan outer, `relatively narrowl end portion 2li having `avertic'ally Adispo-sed, rounded end.2I extendinglong'itudinally"forwardly of the exten- "sions vI'3,.as Shown. The opposite vertical 'sides 4`of,,therela'tively narrow bo'dy'portion 20` are arf ranged 'between the extensions I3 'and secured 40 thereto by welding. Thebody I9 lfurther includes an "inner, `relatively Wide portion 22 .having a Q horizontal, "a't `tcp 'or step 23 arranged at an of the support frame Il), as shown.

4"elevation above 'the v'flat 'top 24 of the relatively narrow ibodyportion "2'0. The opposite -sides-of `'thelbody portion -22 are vertically disposed and converging, andiarranged between the :converging sections I2 and `rigidly' secured theretowby Weldring. .The `vbody or casing IB Vincludes Ian inner,

. kvertical end v25.extendi'ng'ffrom the top 23 to the '5.9

top Yof the vsupport frame In. VThe bottom edge of thebody 4or casing 'I9 yis flushwith'the bottom A narrowy vertical panel :or riser 26 extends transversely {aci-:oss the body its at the .forward :end :of 'the relatively'- jpnrtion .212*andiconnects-thef-tops The inner bars 23 and 24, being secured thereto by welding. The body or casing I9 forms with the support frame I a unitary rigid structure. A caster 21 has its top end pivotally secured to the under side of the top 24, and the caster is arranged within the relatively narrow body portion 20, as shown, and includes a caster Wheel 28 which projects below the bottom of the body I9 and supports the body and adjacent end of the support frame I D approximately two inches above the floor. The caster wheel 28 is preferably slightly larger in diameter than wheels I 8. The caster 21 is disequidistantly between the pairs of wheels I8.

Rigidly secured by welding to the panel 26 and top 24 at opposite ends of the panel 26 are'ver-A tical webs or corner plates 29 having aligned apertures rotatably receiving bottom, opposed, transverse extensions 39 of elongated, straight, parallel, transversely spaced bars v3| of a truck guide handle 32. Rigidly secured to the tops of the bars 3| are opposed, laterally outwardly projecting extensions or handlebars 33, preferably formed integrally with the bars 3|, as shown. The bars 3| are disposed near and upon opposite sides of the longitudinal center line of the truck, and are laterally spaced apart, as shown. The bars 3| are rigidly connected near their top ends by a transverse brace plate 34 welded to the bars, and a similar transverse brace plate 35 is rigidly secured between the bars 3| by welding near the longitudinal centers of the bars. Near and above the lower ends of the bars 3I, a pair of closely spaced locking plates 36 are arranged between the bars and secured thereto by welding. All of the plates 34, 35 and 36 have aligned openings midway between the bars 3I slidably receiving an elongated locking baror bolt 31 having a handle 38 above the plate 34. The bottom end of the locking rod or bolt 31 extends between the locking plates 36 and engages in any one of longitudinally spaced openings 39 of a handle adjusting segment or bar 40, pivotally connected at its bottom end, as shown at 4I, with the top 24 of the body. The handle adjusting segment 40 is arcuate, as shown, and arranged at the transverse center of the truck and midway between the bars 3|, so that the handle 32 maybe adjusted to the desired inclination by engaging the bolt 31 in various ones of the openings 39. The

tion of the support frame IO'beyond the body v'I 9.

The platform 43 includes a flat, rectangular top 44 and opposed, depending, vertical'side 'andend flanges or plates 45 and 46.v 'lhe'platform 43 may also be of Welded construction. When the platform is in the lowered position, the side anges A engage upon the outer longitudinal rails I I" of the frame I9, and the outermost end flange 46 engages upon the transverse bar I4 of the support frame. Near and inwardly of its'opposite ends, the' platform 43 is provided closeto"and belowl its -topv 544 with transverse-i hri'zontah' Vrd- 4 tatable shafts or hinge pins 41 and 48 journaled upon the side flanges 45. Rigidly secured by welding to the hinge. pins 41 and 48 adjacent to the opposite ends of the same are flat, rectangular, depending hinge plates or lifting arms 49 which extend downwardly between the pairs of rails II and I5, and are rigidly secured therebetween by welding to relatively short, horizontal, rotatable, lower shafts or hinge pins 50 journaled upon the pairs of rails I I and I5, as shown. The four plates or lifting arms 49 thus carry the platform 43 bodily, and the lifting arms 49 are swingable vertically to raise and lower the platform 43, maintaining it horizontal at all times. Stop blocks 5I are rigidly secured by welding to the outer faces of the inner rails I5, and these stop blocks are arranged above the hinge pins 5D, Figure 3, for engaging the lifting arms or plates 49 when such arms are in substantially vertical positions to limit the upward travel of the platform 43. A strong, retractile coil spring 52 is provided for biasing the platform 43 in the lowermost position. This spring 52 extends longitudinally of the truck and is arranged at its transverse center. The rear end of the spring is connected with an apertured lug 53 rigidly secured to the adjacent transverse flange 46 of the platform by welding. 'I'he opposite end of the spring 52 is detachably connected with a hook 54 rigidly secured to the transverse bar or brace I6 at the longitudinal center of such brace.

For raising and lowering,r the platform 43, I-

provide a hydraulic jack 55 of conventional construction, and including a body portion or cylininder 55 extending longitudinally of the truck and arrangedat an inclination to the horizontal, as shown. The cylinder 56 vis disposed at the transverse center of the truck and platform 43, and longitudinally slidably mounted within the cylinder is the usual ram or piston rod 51 pivotally connected at 58 with an apertured lug or bracket 59 welded to the adjacent end flange 46 of the platform at the transverse center of the platform. An opening 60 is provided in the end or panel 25 for the ram 51 to operate through, Figure 3. Rigidly secured to the lower end of the cylinder 56, and vpreferably formed integrally therewith, is a transverse base plate 6I having its bottom rigidly secured by welding to a transverse, horizontal hinge pin or shaft 62 journaled at its opposite ends in sleeves or bearings 63 formed upon opposed, longitudinal, horizontal plates 64, in turn rigidly mounted upon the adrjacent Vinner faces of the extensions |3 and rails I5.

Adjacent toone side of the jacklcylinder 56 and rigidly mounted upon the base plate 6I thereof and extending above the base plate 6I is the usual jack pump or actuator 65 including a re. ciprocatory plunger rod 66 operatively connected with an upstanding operating lever 61 pivotally connected with the plunger rod 66 of the pump,as at 68.- The lower'end of the operating lever-61 extends below the pump 65 and is pivotally,;connected, as at 69, with a short link 19 pivotally connected at its lower end with an apertured lug 1I- formedupon the base plate 6I. 'TheV operating Ylever 61 extends lupwardly through the portion 22 of the body I9 and through a longitudinal slot 12 formed in the top 23. The lever 61 is swingable longitudinally in a vertical plane for actuating the pump plunger rod 66 for .extending theram 51 of the jack to raise thezplatform43. yThe hydraulic jack 55 further inclrde's'an exhaust or' control. valve13 having a transverse stem I4 which extends through the adjacent frame section l2 and outwardly of the side of the truck adjacent to the exhaust valve '13, Figure 1. The stem 14 has a handle or knob l5 operable to exhaust the fluid under pressure from the bottom of the cylinder 56 so that the spring 52 may return the elevated platform 43 to its lowermost position.

In use, the handle 32 may be adjusted at the desired inclination, as previously described. This handle is used for pulling or pushing the truck and steering the saine upon the caster 2l. With the platform 43 in its lowermost position and resting upon the top of the support frame l0, the end of the truck having the platform may be rolled beneath a skid loaded with papers or the like to be lifted. The lever 6l is then swung forwardly and rearwardly to actuate the plunger of the jack pump 65 for extending the ram 5l outwardly of the cylinder 56 to the desired amount. The ram 56 will thus elevate the platform 43 the desired amount for lifting the skid from the floor. The upward movement of the platform 53 is limited by the stop blocks 5I which contact the plates or arms 49 when they are substantially vertical. When the loaded skid has been transferred to the desired point, it is merely necessary to turn the knob 15 of the exhaust valve 'i3 and thus release the pressure within the cylinder 55 of the jack so that the spring` 52 may return the platform 43 to the lowered position where it rests upon the support frame I0. When this has been done, the skid will, of course, be returned to the floor. The truck is highly simplified in construction, very compact, exr:

tremely strong and easy to operate.

It is to be understood that the form of my invention herewith shown and described is to be taken as a preferred example of the same, and that various changes in shape, size and arrangement of parts may be resorted to without departing from the spirit of my invention or the scope of the subjoined claims.

Having thus described my invention, I claim:

1. A lifting truck, comprising a low elongated horizontal support frame, wheels mounted upon one end of the support frame for supporting such end, and upstanding casing secured to the op: posite end of the support frame and having its bottom open and projecting above the support frame, a steering caster mounted within the casing and connected with the top of the casing and including a wheel projecting below the casing for supporting the casing and the adjacent end of the support frame, a truck propelling and steering handle connected with the top of the casing and projecting above the casing for a substantial distance, a vertically shiftable lifting platform for the truck and arranged above the frame beyond the casing, vertically swingable hinges connecting the platform and frame, stops secured to the frame for engaging the hinges to limit their upward swinging movement, a spring connecting the platform and frame and serving to bias the platform toward a lowermost position, a hydraulic lifting jack mounted within the casing and having one end pivotally connected with the frame, the jack including a ram having its outer end pivotally connected with one end of the platform to raise and lower the platform, the

casing including an end provided with an opening, the ram operating through said opening when actuated to raise and lower the platform, an upstanding vertically swingable ram operating lever pivotally connected near its lower end with the jack, the top of the casing having a slot formed therein, the upstanding ram actuating lever extending through the slot and above the top of the casing for a substantial distance, the ram actuating lever being arranged near the handle of the truck, and being swingable for extending the ram to raise the platform of the truck, and an exhaust valve for the lifting jack and operable to relieve the pressure behind the ram so that the spring may shift the lifting platform to its lowermost position.

2. A lifting truck comprising a low elongated horizontal support frame, wheels mounted upon one end of the support frame for supporting Such end, and upstanding casing secured to the opposite end of the support frame and having its bottom open and projecting above the support frame, a steering caster mounted within the casing and connected with the top of the casing and including a wheel projecting below the casing for supporting the csing and the adjacent end of the support frame, a truck propelling and steering handle connected with the top of the casing and projecting above the casing for a Substantial distance, a vertically shiftable lifting platform for the truck arranged above the frame beyond the casing, means for connecting the platform and frame for upward swinging movement, stops secured to the frame for engaging the said means to limit said upward swinging movement, a spring connecting the platform and frame and serving to bias the platform toward a lowermost position, a hydraulic lifting jack mounted within the casing and having one end pivotally connected with the frame, the jack including a ram having its outer end pivotally connected with one end of the platform to raise and lower the platform, the casing including an end provided with an opening, the ram operating through said opening when actuated to raise and lower the platform, an upstanding vertically swingable ram operating lever pivotally connected near its lower end with the jack, the ram actuating lever being arranged near the handle of the truck, and being swingable for extending the ram to raise the platform of the truck, and an exhaust valve for the lifting jack and operable to relieve the pressure behind the ram so that the spring may shift the lifting platform to its lowermost position.

JOHN H. KLASSEN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,433,426 Stuebing Oct. 24, 1922 1,480,508 Collis Jan. S, 1924 1,750,277 Moorman Mar. 11, 1930 2,009,970 Hennessy July 30, 1935 2,043,887 Dement June 9, 1936 2,417,396 Framheim Mar. 11, 1947 2,422,538 Framheim June 17, 1947 

